Neuromuscular Disorders USMLE Step 1 Practice Question
A 27-year-old man presents with progressive bilateral leg weakness and paresthesias over 3 days following diarrheal illness 2 weeks prior. Vital signs: BP 138/82, HR 98, RR 20, temp 37.2°C, SpO2 98%. Examination reveals symmetric ascending weakness, areflexia, and intact sensation. Cerebrospinal fluid analysis shows elevated protein (68 mg/dL) with normal cell count. He denies respiratory difficulty. Which of the following is the most likely diagnosis?
Answer choices
- APolymyositis
- BBotulism
- CMultiple sclerosis
- DALS
- EGuillain-Barré syndromeCorrect answer
- FMyasthenia gravis
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